COMFREY comfrey Overview Information

Comfrey is a plant. Even though this plant contains poisonous chemicals called pyrrolizidine alkaloids (PAs), the leaf, root, and root-like stem (rhizome) are used to make medicine. The amount of PAs found in comfrey changes according to the time of harvesting and the age of the plant. The roots have 10 times higher amounts of PAs than the leaves. Some products labeled “common comfrey” or Symphytum officinale actually contain the more poisonous “prickly comfrey” (Symphytum asperum) or “Russian comfrey” (Symphytum x uplandicum) species.

COMFREY comfrey Uses & Effectiveness

Back pain. Applying a specific comfrey extract (Kytta-Salbe f by Merck Selbstmedikation GmbH) to the affected area for 5 days seems to decrease lower or upper back pain.

Osteoarthritis. Applying a specific comfrey extract (Kytta-Salbe f) to the affected area for 3 weeks or applying a specific cream containing comfrey extract, tannic acid, Aloe vera gel, eucalyptus oil, and frankincense oil (4Jointz) to the affected are for 12 weeks seems to decrease pain in people with kneeosteoarthritis.

Sprains. Early research suggests that applying comfrey ointment to the affected area for up to 2 weeks improves mobility, decreases pain, and reduces tenderness and swelling of sprains. The effect of comfrey ointment in relieving pain and reducing swelling seems to be comparable to the effects of diclofenac gel. Most of the studies have used a specific comfrey ointment that is low in pyrrolizidine alkaloids (Kytta-Salbe f).

More evidence is needed to rate the effectiveness of comfrey for these uses.

COMFREY comfrey Side Effects & Safety

Comfrey is POSSIBLY SAFE for most people when applied to unbroken skin in small amounts for less than 10 days. It’s important to remember that the poisonous chemicals in comfrey can pass through the skin. Absorption of these chemicals increases if the skin is broken or if large amounts are applied.

Comfrey is LIKELY UNSAFE for anyone when taken by mouth. It contains chemicals (pyrrolizidine alkaloids, PAs) that can cause liver damage, lung damage, and cancer. The FDA has recommended removal of oral comfrey products from the market.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Comfrey is LIKELY UNSAFE to take by mouth or apply to the skin if you are pregnant or breast-feeding. In addition to causing liver damage and possibly cancer, the PAs in comfrey might also cause birth defects. Even topical use is unwise, since the PAs can be absorbed through the skin.

Broken or damaged skin: Don’t apply comfrey to broken or damaged skin. Doing so might expose you to large amounts of the chemicals in comfrey that can cause liver damage and other serious health effects.

Liver disease: There is a concern that comfrey might make liver disease worse. Don’t use comfrey if you have any problems with your liver.

COMFREY comfrey Interactions

Medications that can harm the liver (Hepatotoxic drugs) interacts with COMFREY

Comfrey might harm the liver. Taking comfrey along with medication that might also harm the liver can increase the risk of liver damage. Do not take comfrey if you are taking a medication that can harm the liver.Some medications that can harm the liver include acetaminophen (Tylenol and others), amiodarone (Cordarone), carbamazepine (Tegretol), isoniazid (INH), methotrexate (Rheumatrex), methyldopa (Aldomet), fluconazole (Diflucan), itraconazole (Sporanox), erythromycin (Erythrocin, Ilosone, others), phenytoin (Dilantin), lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), and many others.

Medications that increase the breakdown of other medications by the liver (Cytochrome P450 3A4 (CYP3A4) inducers) interacts with COMFREY

Comfrey is broken down by the liver. Some chemicals that form when the liver breaks down comfrey can be harmful. Medications that cause the liver to break down comfrey might enhance the toxic effects of chemicals contained in comfrey.Some of these medicines include carbamazepine (Tegretol), phenobarbital, phenytoin (Dilantin), rifampin, rifabutin (Mycobutin), and others.

COMFREY comfrey Dosing

The appropriate dose of comfrey depends on several factors such as the user’s age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for comfrey. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

Conditions of Use and Important Information: This information is meant to supplement, not replace advice from your doctor or healthcare provider and is not meant to cover all possible uses, precautions, interactions or adverse effects. This information may not fit your specific health circumstances. Never delay or disregard seeking professional medical advice from your doctor or other qualified health care provider because of something you have read on WebMD. You should always speak with your doctor or health care professional before you start, stop, or change any prescribed part of your health care plan or treatment and to determine what course of therapy is right for you.

IMPORTANT: About This Section and Other User-Generated Content on WebMD

The opinions expressed in WebMD User-generated content areas like communities, reviews, ratings, or blogs are solely those of the User, who may or may not have medical or scientific training. These opinions do not represent the opinions of WebMD. User-generated content areas are not reviewed by a WebMD physician or any member of the WebMD editorial staff for accuracy, balance, objectivity, or any other reason except for compliance with our Terms and Conditions. Some of these opinions may contain information about treatment or uses of drug products that have not been approved by the U.S. Food and Drug Administration. WebMD does not endorse any specific product, service, or treatment.

Do not consider WebMD User-generated content as medical advice. Never delay or disregard seeking professional medical advice from your doctor or other qualified healthcare provider because of something you have read on WebMD. You should always speak with your doctor before you start, stop, or change any prescribed part of your care plan or treatment. WebMD understands that reading individual, real-life experiences can be a helpful resource but it is never a substitute for professional medical advice, diagnosis, or treatment from a qualified health care provider. If you think you may have a medical emergency, call your doctor or dial 911 immediately.